191 (number)

191 (one hundred [and] ninety-one) is the natural number following 190 and preceding 192.

← 190 191 192 →
Cardinalone hundred ninety-one
Ordinal191st
(one hundred ninety-first)
Factorizationprime
Primeyes
Greek numeralΡϞΑ´
Roman numeralCXCI
Binary101111112
Ternary210023
Octal2778
Duodecimal13B12
HexadecimalBF16

In mathematicsEdit

In astronomyEdit

In geographyEdit

In the militaryEdit

In moviesEdit

In transportationEdit

  • RD-191, a Russian high performance single-combustion chamber rocket engine
  • 191st Street (IRT Broadway – Seventh Avenue Line), a New York City Subway station at St. Nicholas Avenue in Manhattan served by the 1 train
  • At least five known plane crashes have involved flights numbered 191; as a result, the number is considered unlucky in the airline industry and has been withdrawn from use in some airlines

In other fieldsEdit

191 is also:

See alsoEdit

External linksEdit

ReferencesEdit

  1. ^ "Sloane's A069132 : Centered 19-gonal numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-05-28.
  2. ^ Wolfram MathWorld; Primitive Root
  3. ^ "Tables of imaginary quadratic fields with small class number". numbertheory.org.